According to Python library reference, the 2nd/3rd arguments of import should be a dictionary
(whatever globals() or locals() returns), but '' (empty strings) are used instead in some part of the code.
It's not fatal because current CPython implementation does not care what type those argument are,
however, it may change in future, or in alternative Python implementation such as IronPython or Jython
(actually, Jython raises ValueError for __import__(mod, '', '', [''])).